This invention pertains, generally, to pumps of the so-called rotodynamic type which comprise rotary impellers in pump housings, and in particular to a novel impeller for such rotary pumps, and an impeller kit therefor as well.
Rotodynamic pumps are commonly used for the pumping of sewage water, and water in some types of industrial processes which contains fibrous material. It often happens that the pumping is disturbed by rag fibers, and such, which become adhered to the leading edges of the impeller vanes and/or guide vanes. The accretion of such material on the aforesaid edges can cause the pump to vibrate, diminish the efficiency of the pump, and even cause complete clogging. It is sometimes possible to remove the accretion on the leading edges by having the impeller rotate in reverse, but this is not a satisfactory solution to the problem. Another known approach to the problem, to minimize the likelihood of pump clogging, is to provide the pump with some sort of cutting means which disintegrates the pollutants, i.e., the fibrous materials, and such, before they enter the impeller. An example of the latter approach is set forth in Swedish Patent No. 8205774-6. Notwithstanding the merits of this, it occurs that the cutting means wears out and, thereafter, the clogging problem remains.
Clearly, then, there exists a need for a more efficient means for minimizing the accretion of troublesome materials on impeller vanes, and for flushing the vanes with fluid to remove any adhering materials therefrom, and the instant invention is drawn to satisfying that need.